1. Field of the Invention
The present invention relates to a parallel link robot which facilitates position calibration work.
2. Description of the Related Art
A δ-type parallel link robot is known in which three servo motors are arranged on a base, arms (links) are connected to output shafts of the servo motors, and an operating head (moving part) is displaced in the 3D space below the base by driving the arms. In this type of parallel link robot, in order to secure positional precision of the operating head, the arms have to be moved in advance to predetermined positions to calibrate the servo motors. In the parallel link robot which is described in Japanese Patent No. 4822558 (JP4822558B), origin pins are projected from motor brackets, reference pins are projected from the base ends of the arms, and the states where the reference pins abut against the origin pins are used as the origin positions of the links for carrying out the position calibration work.
However, in the parallel link robot which is described in JP4822558B, when driving the arms to make the reference pins abut against the origin pins, the arms are liable to be mistakenly driven too much. If the arms are driven too much, the abutting force between the reference pins and the origin pins becomes excessive and damage to the parallel link robot may be invited.